CN103043668A - Preparation method of core additive - Google Patents
Preparation method of core additive Download PDFInfo
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- CN103043668A CN103043668A CN2011103097804A CN201110309780A CN103043668A CN 103043668 A CN103043668 A CN 103043668A CN 2011103097804 A CN2011103097804 A CN 2011103097804A CN 201110309780 A CN201110309780 A CN 201110309780A CN 103043668 A CN103043668 A CN 103043668A
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Abstract
The invention relates to a preparation method of a core additive, which sequentially comprises the following steps: heating liquid silicasol to 500+/-100 DEG C, keeping the temperature for 2-6 hours, and carrying out furnace cooling on the material to room temperature; weighing the obtained solid, adding the solid into a ball grinder, adding a grinding body according to the weight ratio of 1:(0.7-1.5), carrying out ball grinding for 8-10 hours, and passing through a 150-250-mesh screen to obtain powder; carrying out high-temperature calcination on the powder at 1100-1250 DEG C for 3-10 hours, and carrying out furnace cooling on the material; and weighing the material, adding into a ball grinder, adding a grinding body according to the weight ratio of 1:(0.7-1.5), and carrying out ball grinding for 4-15 hours to obtain amorphous silica core additive powder of which the grain diameter is 7-60 mu m. The silyl core prepared from the amorphous silica additive has the advantages of large specific area and high core pressure molding rate, and enhances the suspensibility and flowability of the core slurry; the sintering characteristic is good; the room-temperature strength and high-temperature strength of the core are high; and the core is easy to strip, and the casting qualification rate is up to 70%.
Description
Technical field
The present invention relates to a kind of preparation technology of ceramic core additive, it has improved especially a kind ofly can improve ceramic core room temperature strength and hot strength, reduces the preparation method of the additive of high temperature deformation.
Background technology
Along with improving constantly of inlet temperature before the engine turbine, blade to hold warm Capability Requirement more and more higher.Adopt the hollow blade of the precision casting technology preparation of ceramic core, the inner chamber road shape is complicated, and the warm ability of holding of blade is improved, uniformity of temperature profile, the work-ing life of prolongation blade.The working conditions of ceramic core is very abominable, needs higher room temperature strength and hot strength.The silica-based core that adopts at present, in the pressing process easily break in thinner and small place, and flexural strength was low when teeming temperature improved, and the qualified cast rate is low.Simultaneously, along with engine manufacturing technology improves constantly, higher to manufacturing technology and the performance index requirement of core, existing silica-based core does not satisfy the founding requirement, and the new technological method of active demand improves the performance index of core.
Summary of the invention
This purpose provides the preparation method of the better core additive of a kind of technique effect.Key is to improve room temperature strength and the hot strength of core, controls better separating out of cristobalite content in the plasticity of core pressing process and the roasting process, reduces crackle and the distortion of core.By adding the voluntarily soft silica of development, improved the reactivity on core powder surface, the distortion of core hygrometric state reduces, and room temperature strength, hot strength and sintering character improve.
The invention provides a kind of preparation method of core additive, it is characterized in that: the preparation method of described core additive requires as follows successively:
1. step at first is heated to 500 ± 100 ℃ with liquid-state silicon colloidal sol, is incubated 2-6 hour, and then material cools to room temperature with the furnace;
2. step weighs a upper process gained solid, puts into ball mill, by weight 1:(0.7-1.5) add grinding element, Ball-milling Time 8 ~ 10h crosses the 150-250 mesh sieve, crosses grinding element and obtains powder;
Step 3., the powder that a upper process is obtained carries out high-temperature calcination under 1100 ℃ of-1250 ℃ of conditions, soaking time is 3-10 hour, the material furnace cooling;
4. step with the material metage after the high-temperature calcination, puts into ball mill, by weight 1:(0.7-1.5) add the grinding element ball milling, Ball-milling Time 4-15h, the soft silica core additive powder of acquisition, particle size diameter is 7-60 μ m.
The preparation method of core additive of the present invention, preferably satisfy following requirement:
1. step is heated to 500 ± 20 ℃ with liquid-state silicon colloidal sol, is incubated 3.5-5 hour, and then material cools to room temperature with the furnace;
2. step weighs a upper process gained solid, puts into ball mill, by weight 1:(0.9-1.1) add grinding element, Ball-milling Time 8 ~ 10h crosses 200 mesh sieves, crosses grinding element and obtains powder;
Step 3., the powder that a upper process is obtained carries out high-temperature calcination under 1160 ℃ of-1200 ℃ of conditions, soaking time is 3.5-5 hour, the material furnace cooling;
4. step with the material metage after the high-temperature calcination, puts into ball mill, by weight 1:(0.9-1.1) adding grinding element ball milling, the core additive powder particles diameter of Ball-milling Time and acquisition satisfies one of following requirement: one, Ball-milling Time 4 ~ 6h, particle size diameter are 50 ~ 60 μ m; Its two, Ball-milling Time 7 ~ 10h, particle size diameter are 30 ~ 20 μ m; Its three, Ball-milling Time 11 ~ 15h, particle size diameter are 20 ~ 10 μ m.
The preparation method of core additive of the present invention, further preferably satisfy following requirement:
Satisfy following requirement among the preparation method of described core additive:
1. step packs liquid-state silicon colloidal sol in the clean stainless steel cask into, puts into electrically heated drying cabinet and is heated to 500 ℃, is incubated 4 hours, and then material cools to room temperature with the furnace;
2. step weighs a upper process gained solid, puts into ball mill, adds grinding element by weight 1:1, and Ball-milling Time 9h crosses 200 mesh sieves, crosses grinding element and obtains powder;
3. step puts into ceramic disc with the powder that a upper process obtains, and in the chamber type electric resistance furnace of packing into, carries out high-temperature calcination under 1160 ℃ of-1200 ℃ of conditions, and soaking time is 4 hours, the material furnace cooling;
4. step with the material metage after the high-temperature calcination, puts into ball mill, add the grinding element ball milling by weight 1:1, the core additive powder particles diameter of Ball-milling Time and acquisition satisfies one of following requirement: one, Ball-milling Time 4 ~ 6h, particle size diameter are 50 ~ 60 μ m; Its two, Ball-milling Time 7 ~ 10h, particle size diameter are 30 ~ 20 μ m; Its three, Ball-milling Time 11 ~ 15h, particle size diameter are 20 ~ 10 μ m.
The silica-based core that adds the soft silica additive of the present invention's preparation, through evidence:
1, the soft silica powder contains many micropores, specific surface area is large, has improved suspension and the flowability of core slurry, and core compression moulding rate improves.
2, soft silica micro mist material can fully be filled in the core substrate material particle slit, promotes the core sintering character, has reduced crackle and the distortion of core, and the room temperature strength of core and hot strength improve.
3, the soft silica powder can promote cristobalite.Add a certain amount of additive in silica glass, cristobalite content increases in the core after the roasting, and core warp resistance deformability improves.
Step 3. in, adopt different calcining temperatures, can detect the inversion quantity of cristobalite under the differing temps.Test-results shows when the high-temperature calcination temperature is 1200 ℃, have a small amount of cristobalite to separate out.When calcining temperature was 1180 ℃ and 1190 ℃, the gained material had preferably surfactivity, and separates out without cristobalite, and material is soft silica.Amorphous silica particles contains many micropores, and good surface activity adds certain soft silica additive at the quartz glass substrate material, can improve the reactivity on powder surface.In the compacting core, improved suspension and the flowability of core slurry, be easy to press forming.In roasting process, easy-sintering.In casting process, the soft silica powder can promote the cristobalite growth, improves core hot strength and high temperature anti-crawl agentdefiection and deformability.
Material after the high-temperature calcination is that 50 ~ 40 μ m, 30 ~ 20 μ m and 20 ~ 10 μ m grinding are sieved by size-grade distribution.Soft silica micro mist material can fully be filled in the core substrate material particle slit, promotes the core sintering character, improves room temperature strength and the hot strength of core.Test-results shows that size-grade distribution is the performance that the additive of 20 ~ 10 μ m significantly improves silica-based core, makes it have good room temperature strength, hot strength and sintering character.
Use the soft silica additive of the present invention's preparation, room temperature strength and the hot strength of silica-based core significantly improve, and core has good coking property, is easy to depoling, and the cast qualification rate brings up to 70% by 30 ~ 50%.
Description of drawings
The present invention is further detailed explanation below in conjunction with drawings and the embodiments:
Fig. 1 leads core for the II of restriking of adding soft silica; Because core structure is complicated, in the pressing process easily break in thinner and small place; The soft silica additive can improve the reactivity on powder surface; In the compacting core, improved suspension and the flowability of core slurry, be easy to press forming;
Fig. 2 is the directional vane core; Because directional vane requires to have higher high temperature bend strength with core in the crystal pulling process, soft silica additive powder can fully be filled in the core substrate material particle slit, promotes the core sintering character, improved the high-temperature behavior of core, the blade casting qualification rate significantly improves;
Fig. 3 is the single crystal blade core; Single crystal blade requires to have high hot strength and good depoling performance with core; Soft silica additive powder can fully be filled in the core substrate material particle slit, promotes the core sintering character, makes core have good hot strength, and is easy to depoling.
Embodiment
Embodiment 1
Satisfy following requirement among the preparation method of described core additive:
1. step packs liquid-state silicon colloidal sol in the clean stainless steel cask into, puts into electrically heated drying cabinet and is heated to 500 ℃, is incubated 4 hours, and then material cools to room temperature with the furnace;
2. step weighs a upper process gained solid, puts into ball mill, adds grinding element by weight 1:1, and Ball-milling Time 9h crosses 200 mesh sieves, crosses grinding element and obtains powder;
3. step puts into ceramic disc with the powder that a upper process obtains, and in the chamber type electric resistance furnace of packing into, carries out high-temperature calcination under 1160 ℃ of-1200 ℃ of conditions, and soaking time is 4 hours, the material furnace cooling;
4. step with the material metage after the high-temperature calcination, puts into ball mill, add the grinding element ball milling by weight 1:1, the core additive powder particles diameter of Ball-milling Time and acquisition satisfies one of following requirement: one, Ball-milling Time 4 ~ 6h, particle size diameter are 50 ~ 60 μ m; Its two, Ball-milling Time 7 ~ 10h, particle size diameter are 30 ~ 20 μ m; Its three, Ball-milling Time 11 ~ 15h, particle size diameter are 20 ~ 10 μ m.
Soft silica after the high-temperature calcination that the above-mentioned preparation process of employing process obtains obtains the silica-based core of equiax crystal blade as additive by following prescription compacting.
The equiax crystal blade is with silica-based core prescription: silica additive: weight percent 10-20%; Fused silica powder+mineralizer: weight percent is surplus.
The equiax crystal blade selects the II of restriking to lead to be carrier with silica-based core, and adopting the soft silica after the high-temperature calcination is additive, by above-mentioned prescription compacting core.The II of restriking is led core structure complexity (as shown in Figure 1), and in the pressing process easily break in thinner and small place, and the soft silica additive has improved suspension and the flowability of slurry, makes core have good wet strength, and plasticity improves.
Embodiment 2
Satisfy following requirement among the preparation method of described core additive:
1. step packs liquid-state silicon colloidal sol in the clean stainless steel cask into, puts into electrically heated drying cabinet and is heated to 520 ℃, is incubated 4 hours, and then material cools to room temperature with the furnace;
2. step weighs a upper process gained solid, puts into ball mill, adds grinding element by weight 1:1.1, and Ball-milling Time 10h crosses 150 mesh sieves, crosses grinding element and obtains powder;
3. step puts into ceramic disc with the powder that a upper process obtains, and in the chamber type electric resistance furnace of packing into, carries out high-temperature calcination under 1160 ℃ of-1200 ℃ of conditions, and soaking time is 5 hours, the material furnace cooling;
4. step with the material metage after the high-temperature calcination, puts into ball mill, add the grinding element ball milling by weight 1:1.1, the core additive powder particles diameter of Ball-milling Time and acquisition satisfies one of following requirement: one, Ball-milling Time 4 ~ 6h, particle size diameter are 50 ~ 60 μ m; Its two, Ball-milling Time 7 ~ 10h, particle size diameter are 30 ~ 20 μ m; Its three, Ball-milling Time 11 ~ 15h, particle size diameter are 20 ~ 10 μ m.
Soft silica after the high-temperature calcination that the above-mentioned preparation process of employing process obtains obtains the silica-based core of directional vane as additive by following prescription compacting.
Directional vane is with silica-based core prescription: silica additive: weight percent 5-15%; Fused silica powder+mineralizer: weight percent is surplus.
Directional vane is prepared core powder, compacting core with silica-based core by above-mentioned prescription.Because directional vane requires to have more high bending strength with core in the crystal pulling process, soft silica additive powder can fully be filled in the core substrate material particle slit, promotes the core sintering character, improve the high-temperature behavior of core, improved the blade casting qualification rate.
Embodiment 3
Satisfy following requirement among the preparation method of described core additive:
1. step packs liquid-state silicon colloidal sol in the clean stainless steel cask into, puts into electrically heated drying cabinet and is heated to 480 ℃, is incubated 3.5 hours, and then material cools to room temperature with the furnace;
2. step weighs a upper process gained solid, puts into ball mill, adds grinding element by weight 1:0.9, and Ball-milling Time 8h crosses 250 mesh sieves, crosses grinding element and obtains powder;
3. step puts into ceramic disc with the powder that a upper process obtains, and in the chamber type electric resistance furnace of packing into, carries out high-temperature calcination under 1160 ℃ of-1200 ℃ of conditions, and soaking time is 3.5 hours, the material furnace cooling;
4. step with the material metage after the high-temperature calcination, puts into ball mill, add the grinding element ball milling by weight 1:0.9, the core additive powder particles diameter of Ball-milling Time and acquisition satisfies one of following requirement: one, Ball-milling Time 4 ~ 6h, particle size diameter are 50 ~ 60 μ m; Its two, Ball-milling Time 7 ~ 10h, particle size diameter are 30 ~ 20 μ m; Its three, Ball-milling Time 11 ~ 15h, particle size diameter are 20 ~ 10 μ m.
Soft silica after the high-temperature calcination that the above-mentioned preparation process of employing process obtains obtains the silica-based core of single crystal blade as additive by following prescription compacting.
Single crystal blade is with silica-based core prescription: silica additive: weight percent 1-10%; Fused silica powder+mineralizer: weight percent is surplus.
Single crystal blade is prepared core powder, compacting core with silica-based core by above-mentioned prescription.Single crystal blade requires to have high hot strength and good depoling performance with core.Soft silica additive powder can fully be filled in the core substrate material particle slit, promotes the core sintering character, makes core have good hot strength, and is easy to depoling.
Claims (3)
1. the preparation method of a core additive, it is characterized in that: the preparation method of described core additive requires as follows successively:
1. step at first is heated to 500 ± 100 ℃ with liquid-state silicon colloidal sol, is incubated 2-6 hour, and then material cools to room temperature with the furnace;
2. step weighs a upper process gained solid, puts into ball mill, by weight 1:(0.7-1.5) add grinding element, Ball-milling Time 8-10h crosses the 150-250 mesh sieve, crosses grinding element and obtains powder;
Step 3., the powder that a upper process is obtained carries out high-temperature calcination under 1100 ℃ of-1250 ℃ of conditions, soaking time is 3-10 hour, the material furnace cooling;
4. step with the material metage after the high-temperature calcination, puts into ball mill, by weight 1:(0.7-1.5) add the grinding element ball milling, Ball-milling Time 4-15h, the soft silica core additive powder of acquisition, particle size diameter is 7-60 μ m.
2. according to the preparation method of the described core additive of claim 1, it is characterized in that: satisfy following requirement among the preparation method of described core additive:
1. step is heated to 500 ± 20 ℃ with liquid-state silicon colloidal sol, is incubated 3.5-5 hour, and then material cools to room temperature with the furnace;
2. step weighs a upper process gained solid, puts into ball mill, by weight 1:(0.9-1.1) add grinding element, Ball-milling Time 8-10h crosses 200 mesh sieves, crosses grinding element and obtains powder;
Step 3., the powder that a upper process is obtained carries out high-temperature calcination under 1160 ℃ of-1200 ℃ of conditions, soaking time is 3.5-5 hour, the material furnace cooling;
4. step with the material metage after the high-temperature calcination, puts into ball mill, by weight 1:(0.9-1.1) adding grinding element ball milling, the core additive powder particles diameter of Ball-milling Time and acquisition satisfies one of following requirement: one, Ball-milling Time 4-6h, particle size diameter are 50-60 μ m; Its two, Ball-milling Time 7-10h, particle size diameter are 30-20 μ m; Its three, Ball-milling Time 11-15h, particle size diameter are 20-10 μ m.
3. according to the preparation method of the described core additive of claim 1, it is characterized in that: satisfy following requirement among the preparation method of described core additive:
1. step packs liquid-state silicon colloidal sol in the clean stainless steel cask into, puts into electrically heated drying cabinet and is heated to 500 ℃, is incubated 4 hours, and then material cools to room temperature with the furnace;
2. step weighs a upper process gained solid, puts into ball mill, adds grinding element by weight 1:1, and Ball-milling Time 9h crosses 200 mesh sieves, crosses grinding element and obtains powder;
3. step puts into ceramic disc with the powder that a upper process obtains, and in the chamber type electric resistance furnace of packing into, carries out high-temperature calcination under 1160 ℃ of-1200 ℃ of conditions, and soaking time is 4 hours, the material furnace cooling;
4. step with the material metage after the high-temperature calcination, puts into ball mill, add the grinding element ball milling by weight 1:1, the core additive powder particles diameter of Ball-milling Time and acquisition satisfies one of following requirement: one, Ball-milling Time 4-6h, particle size diameter are 50-60 μ m; Its two, Ball-milling Time 7-10h, particle size diameter are 30-20 μ m; Its three, Ball-milling Time 11-15h, particle size diameter are 20-10 μ m.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CZ305385B6 (en) * | 2013-07-08 | 2015-08-26 | Sedlecký kaolin a.s. | Method of obtaining white calcined filling agent, grog or lightening agent with high reflective capacity |
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| US4989664A (en) * | 1988-07-07 | 1991-02-05 | United Technologies Corporation | Core molding composition |
| CN1793011A (en) * | 2005-11-29 | 2006-06-28 | 辽宁省轻工科学研究院 | Composite ceramic core material adopting nano silicon dioxide |
| CN1830774A (en) * | 2005-09-15 | 2006-09-13 | 成都理工大学 | Method of preparing high purity spherical nanometer noncrystalline silicon micropowder using natural powder quartz |
| CN101033068A (en) * | 2007-02-13 | 2007-09-12 | 袁茂豪 | Method of preparing high-purity ultra-fine sphere silicon micro-powder |
| CN102079653A (en) * | 2010-12-06 | 2011-06-01 | 北京航空航天大学 | Method for producing silicon-based ceramic core for aircraft engine blade |
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2011
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Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4093017A (en) * | 1975-12-29 | 1978-06-06 | Sherwood Refractories, Inc. | Cores for investment casting process |
| US4989664A (en) * | 1988-07-07 | 1991-02-05 | United Technologies Corporation | Core molding composition |
| CN1830774A (en) * | 2005-09-15 | 2006-09-13 | 成都理工大学 | Method of preparing high purity spherical nanometer noncrystalline silicon micropowder using natural powder quartz |
| CN1793011A (en) * | 2005-11-29 | 2006-06-28 | 辽宁省轻工科学研究院 | Composite ceramic core material adopting nano silicon dioxide |
| CN101033068A (en) * | 2007-02-13 | 2007-09-12 | 袁茂豪 | Method of preparing high-purity ultra-fine sphere silicon micro-powder |
| CN102079653A (en) * | 2010-12-06 | 2011-06-01 | 北京航空航天大学 | Method for producing silicon-based ceramic core for aircraft engine blade |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CZ305385B6 (en) * | 2013-07-08 | 2015-08-26 | Sedlecký kaolin a.s. | Method of obtaining white calcined filling agent, grog or lightening agent with high reflective capacity |
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Address after: 110043 Dong TA street, Dadong District, Shenyang, Liaoning Province, No. 6 Patentee after: Chinese Hangfa Shenyang Liming Aero engine limited liability company Address before: 110043 Dong TA street, Dadong District, Shenyang, Liaoning Province, No. 6 Patentee before: Liming Aeroplane Engine (Group) Co., Ltd., Shenyang City |
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